Wyniki wyszukiwania - BazTech

Ograniczanie wyników

1 Environment Protection Engineering

1 2005

Znaleziono wyników: 1

Liczba wyników na stronie

Wyniki wyszukiwania

Wyszukiwano:
w słowach kluczowych: non-circular membranes

Sortuj według:

Ogranicz wyniki do:

Non-circular ceramic membranes for use in wastewater treatment

Chiu T. Y., Lara Dominguez M. V., James A. E.

Environment Protection Engineering

2005

Vol. 31, nr 3-4

53-60

An extensive use of membrane bioreactors in wastewater treatment often produces the effluent quality far beyond the current regulatory requirements for discharge to the environment. However, like other processes involving membranes, the severest constraint is the problem of fouling, the extent of which can be reduced by changing the flow pattern (maintaining in turbulent conditions) within the channels. In this study, the treatment of effluent from synthetic sludge production was investigated employing membrane bioreactors utilising non-circular multi-channelled membranes. Very high chemical oxygen demand (COD) and suspended solids (SS) removals were obtained for the range of pore sizes employed, up to 94% and 98%, respectively. As the pore size was increased, a decrease in efficiency was observed. Differences in the rejection behaviour are attributed to the difference in the characteristics of cakes which were formed. Specific cake resistance seems to increase moderately with diminishing pore size. The critical flux was found to be dependent on cross-flow velocity, introduction of inserts and pore size. Critical flux increased to about 82.5 l m-2 h-1 at a cross-flow velocity of 2.0 m s-1. The high critical flux can be attributed to the non-circular geometry of the channels which seems to promote turbulent flow, depolarising the solute built-up, even at low cross-flow velocity. Finally, the present paper demonstrates ways in which hydrodynamics and colloid interactions affect the critical flux.